:root {
    --primary-color: #1a237e;
    /* Navy */
    --accent-color: #e65100;
    /* Orange */
    --text-color: #333333;
    --bg-color: #f8f9fa;
    --white: #ffffff;
    --border-color: #e0e0e0;
    --font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, 'Helvetica Neue', 'Segoe UI', 'Apple SD Gothic Neo', 'Noto Sans KR', 'Malgun Gothic', 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol', sans-serif;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-family);
    color: var(--text-color);
    background-color: var(--bg-color);
    line-height: 1.6;
}

a {
    text-decoration: none;
    color: inherit;
}

/* Header */
.site-header {
    background-color: var(--white);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.home-link {
    font-size: 0.9rem;
    color: #666;
    font-weight: 500;
    transition: color 0.2s;
}

.home-link:hover {
    color: var(--primary-color);
}

.site-header h1 {
    font-size: 1.1rem;
    color: var(--primary-color);
    font-weight: 700;
}

/* Main Container */
.article-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 1.5rem;
}

/* Article */
.post {
    background-color: var(--white);
    padding: 2.5rem;
    border-radius: 12px;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.05);
}

.post-header {
    margin-bottom: 2rem;
    text-align: center;
}

.category {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background-color: rgba(230, 81, 0, 0.1);
    color: var(--accent-color);
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 20px;
    margin-bottom: 1rem;
}

.post-title {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    line-height: 1.3;
}

.post-meta {
    color: #888;
    font-size: 0.9rem;
}

/* TOC */
.toc-container {
    background-color: #f8f9fa;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 2.5rem;
}

.toc-title {
    font-weight: 700;
    margin-bottom: 0.75rem;
    font-size: 1.1rem;
    color: var(--primary-color);
}

#toc-list {
    list-style: none;
}

#toc-list li {
    margin-bottom: 0.5rem;
}

#toc-list a {
    color: #555;
    font-size: 0.95rem;
    transition: color 0.2s;
    display: block;
}

#toc-list a:hover {
    color: var(--accent-color);
    text-decoration: underline;
}

#toc-list .toc-sub {
    margin-left: 1.2rem;
    font-size: 0.9rem;
}

/* Content */
.post-content {
    font-size: 1.05rem;
}

.post-content h2 {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-top: 2.5rem;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #f0f0f0;
}

.post-content h3 {
    font-size: 1.25rem;
    color: #333;
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
}

.post-content p {
    margin-bottom: 1.2rem;
    color: #444;
}

/* Tables */
.table-container {
    overflow-x: auto;
    margin-bottom: 2rem;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.95rem;
    min-width: 500px;
}

th,
td {
    padding: 0.75rem 1rem;
    border-bottom: 1px solid var(--border-color);
    text-align: left;
}

th {
    background-color: #f1f3f5;
    font-weight: 600;
    color: var(--primary-color);
}

tr:last-child td {
    border-bottom: none;
}

/* Highlights */
strong {
    font-weight: 700;
    color: #111;
}

.highlight {
    background-color: rgba(255, 235, 59, 0.3);
    padding: 0 2px;
}

/* Ad Banner */
.ad-banner {
    background-color: #f8f9fa;
    border: 1px dashed #ccc;
    padding: 1rem;
    margin: 2.5rem 0;
    text-align: center;
    min-height: 100px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #888;
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
    .post {
        padding: 1.5rem;
    }

    .post-title {
        font-size: 1.6rem;
    }

    .article-container {
        padding: 1rem;
    }

    .post-content h2 {
        font-size: 1.35rem;
    }
}

/* CTA Button */
.cta-container {
    margin-top: 4rem;
    text-align: center;
    padding: 3rem 1.5rem;
    background-color: #f1f8e9;
    border-radius: 16px;
    border: 1px solid #c5e1a5;
}

.cta-text {
    font-size: 1.1rem;
    font-weight: 600;
    color: #33691e;
    margin-bottom: 1.5rem;
}

.cta-button {
    display: inline-block;
    background-color: var(--accent-color);
    color: var(--white);
    font-size: 1.1rem;
    font-weight: 700;
    padding: 1rem 2rem;
    border-radius: 50px;
    box-shadow: 0 4px 12px rgba(230, 81, 0, 0.3);
    transition: transform 0.2s, box-shadow 0.2s, background-color 0.2s;
}

.cta-button:hover {
    background-color: #ef6c00;
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(230, 81, 0, 0.4);
}